Volkswagen UK boss Paul Willis has admitted that his company's so-called 'defeat device' did affect the results of emissions tests in Europe.
Previously, the German manufacturer has only confirmed that the software-based emissions cheat was present on some vehicles in Europe - and has not outlined whether the defeat device was active during the NEDC emissions test used across the EU.
However, when asked during a 45-minute grilling from MPs on the transport select committee if the defeat device had been used during type approval testing for the UK, Willis admitted, "It seems from what I understand - and I'm not an engineer - that the system of gas regulation in the engine influenced the NOx output in cars that we sell in the UK. These cars are type approved across all of Europe, of course, and they're type approved in Germany, with separate people overlooking it.
"We mishandled the situation in so far as our engines behaved differently within the testing regime to the real world. That's why we need to fix the cars, that's why we need to get the customers in, and that's why we need to put the cars right. We mishandled the situation, without a shadow of a doubt.
"It seems that in the test regime the engine behaved differently to the real-world situation via software. The software affected the flow of gas to the engine which reduced the NOx."
UK's 1.6 diesel fix won't need a new urea tank
Of the 1.2 million affected cars in the UK, Willis said 400,000 - believed to be those with the 1.6-litre version of the EA189 diesel engine - would need additional corrective work beyond a software upgrade, including new fuel injectors, and that this would "take a longer period of time".
However, he said that the installation of exhaust after-treatments, likely to be fitted to some cars affected in the US in the form of a urea tank, would not be necessary in the UK. "My understanding is that the addition of urea tanks is not part of the solution in Europe," he stated. "There's a different technical configuration on the cars and different technical regulations apply. My understanding is that the costs are different, too."
The remaining 700,000-odd units - 2.0-litre diesels and around 30,000 1.2-litre diesels - can be fixed by software patches alone.
While details on the technical fix Volkswagen will use to correct the affected cars remain limited, Willis said that customers should notice no difference in fuel economy once the fix has been applied. "Our engineers are working to the brief that there cannot be any change in miles per gallon," he said.
Willis said VW reacted "as quickly as possible"
The session at the House of Commons was the first opportunity for the transport select committee - a cross-party body made up of 11 MPs - to question VW representatives or the car industry on the dieselgate scandal.
Willis came under particular pressure on the amount of time taken by VW UK to remove affected vehicles - around 4000 cars still on the market - from sale. He argued that the firm had acted as quickly as possible, saying, "On 22nd September we were made aware by VW headquarters in Wolfsburg that there was a potential problem with diesel engines. On 28th September we were getting more details and I phoned Mr McLoughlin [Patrick McLoughin, the Transport Secretary] to say to him that as soon as I knew which vehicles were affected, I would voluntarily stop selling those cars. That phone call took place at 3pm on 28th September.
"On 30th September, at 9am in the morning, I received the VIN numbers from the various different factories. And this is the point: there were eight days between when we first knew it affected Europe and when I stopped selling cars. And the reason for that is the complexity of the number of cars involved. There are 60 different models, five different brands, three different engines and two different transmissions.
"I found the VIN numbers out precisely at 9am, and at 1.30pm, once I had clarified it with the computer systems, I stopped selling those cars voluntarily. It took four hours and 30 minutes from the time I knew the affected cars until I took action - four hours and 30 minutes."
Existing test comes under fire from MPs
Both Willis and the chief executive of the Society of Motor Manufacturers and Traders, Mike Hawes, were asked if the current emissions testing procedure was fit for purpose. Hawes admitted that the difference between real-world figures and those provided by the NEDC could be "up to 30%". "These figures are meant for a comparison process and always contain a disclaimer about the real world and this is for some very sensible comparitive reasons," he said.
"The test cycle dates back to the early 1980s and the industry recognises it isn't fit for purpose," he added. "When you put a vehicle on the test cycle, for instance, all of the electronic devices that you would turn on in the real world - air-conditioning, heating, sat-nav, Bluetooth - all of that has to be switched off, by law, because when the regulation was created that sort of technology wasn't available. Then there's the issue of real-world driving conditions - congestion, temperature, load, gradient - all huge and all ruled out by the test cycle to get a repeatable cycle."
Hawes said he believes a more realistic testing cycle will be introduced on a compulsory basis from the beginning of 2017.
Willis also criticised the current testing procedure. He said: "If we look at the test regime on emissions, we know it is old-fashioned and not fit for purpose. We need completely independent tests that look at all sorts of detail, like Euro NCAP, which uses real-world testing. We need to look at that."
"We have a duty to the public to reassure them [customers] that our cars are safe. There is no relation to safety with this issue but we do need to regain trust and we will do that with transparency."
Willis also apologised to VW customers in the UK saying: "Volkswagen has significantly let down its customers and the wider public. We recognise we've fallen short of the standards expected and we will take all the necessary steps to regain trust."
The scale of VW's global problem
In total, VW has said that just under 11 million vehicles worldwide have the software 'defeat device' that was exposed in American emissions tests last month. While two-thirds are thought to be fixable with a software upgrade, it's believed that a total of 3.6 million affected VW, Audi, Skoda and Seat models - those featuring the 1.6-litre version of the EA189 turbodiesel engine - will require hardware changes to correct the issue. US models may require the addition of a urea tank, whereas European editions of the 1.6 are likely to need new fuel injectors.
VW's new CEO Matthias Müller has pledged that all affected cars will be fixed by the end of next year. He added: "Our most important task will be to regain lost confidence with our customers, partners, investors and the general public. The first step in this direction will be a fast and relentless examination and explanation. Only when everything comes to the table, only when things are completely explained, only then will people trust us again.
"Believe me, I too am impatient. But in this situation, in which we are dealing with four brands and many models, care is more important than speed.
"The technical solutions to the problems are in sight. By contrast, the business and financial consequences are not yet foreseeable."